The background art related to the above-mentioned technical field is described in PATENT LITERATURE 1 and PATENT LITERATURE 2. Described in PATENT LITERATURE 1 is a molded module that is obtained when a plurality of terminals forming a wiring and a plurality of electronic parts mounted on the individual terminals are molded with molding resin. At least some of the plurality of terminals are exposed from the back surface of molding resin. An electric motor case to which the molded module is fastened is a case that is disposed toward a speed-reducing mechanism and fastened to the speed-reducing mechanism.
Described in PATENT LITERATURE 2 is a power module that includes a heat dissipation layer, an insulating layer, a current circuit wiring section, a plurality of switching elements, a plurality of external terminals, and resin. The heat dissipation layer includes a first principal surface and a second principal surface that is positioned opposite the first principal surface. The insulating layer is disposed on the first principal surface of the heat dissipation layer. The current circuit wiring section is provided for the insulating layer. The plurality of switching elements are disposed on the insulating layer and electrically connected to the current circuit wiring section. The plurality of external terminals are electrically connected to the current circuit wiring section. The resin seals the insulating layer, the current circuit wiring section, the switching elements, the whole of the first principal surface of the heat dissipation layer, and a part of the second principal surface of the heat dissipation layer. The power module is connected to a power module mount of a motor.